Certain surgical procedures require the surgeon to perform delicate surgical operations on tissues within the body that are moving or otherwise unstable. The ability to stabilize or immobilize a surgical site provides greatly improved surgical accuracy and precision and reduces the time required to complete a particular procedure. A large and growing number of surgeons are performing successful coronary artery bypass graft (CABG) surgery on the beating heart by temporarily stabilizing or immobilizing a localized area of the beating heart. Methods and apparatus for performing a CABG procedure on a beating heart are described in U.S. Pat. Nos. 5,894,843 and 5,727,569 to Benetti et al., both of which are incorporated herein, in their entireties, by reference thereto.
In a typical CABG procedure, a blocked or restricted section of coronary artery, which normally supplies blood to some portion of the heart, is bypassed using a source vessel or graft vessel to re-establish blood flow to the artery downstream of the blockage. This procedure requires the surgeon to create a fluid connection, or anastomosis, between the source or graft vessel and an arteriotomy or incision in the coronary artery. Forming an anastomosis between two vessels in this manner is a particularly delicate procedure requiring the precise placement of tiny sutures in the tissue surrounding the arteriotomy in the coronary artery and the source or graft vessel.
The rigors of creating a surgical anastomosis between a coronary artery and a source vessel or graft vessel demands that the target site for the anastomosis be substantially motionless. To this end, a number of devices have been developed which are directed to stabilizing a target site on the beating heart for the purpose of completing a cardiac surgical procedure, such as completing an anastomosis. Stabilization may be provided using a device that provides a mechanical or compression force to the tissue or by a device which applies a negative pressure or suction to the tissue. Representative devices useful for stabilizing a beating heart are described, for example, in U.S. Pat. Nos. 5,894,843; 5,727,569; 5,836,311 and 5,865,730, each of which is incorporated herein, in its entirety, by reference thereto.
As beating heart procedures have evolved, regardless of whether compression or negative pressure has been used to stabilize or immobilize the heart, new challenges have arisen. For example, surgeons may gain access to the heart using a number of different approaches, both open and closed chest, such as through a sternotomy, mini-sternotomy, thoracotomy or mini-thoracotomy, or less invasively through a port provided within the chest cavity of the patient, e.g., between the ribs or in a subxyphoid area, with or without the visual assistance of a thoracoscope. Accordingly, the devices used to stabilize the heart must be configured to accommodate the particular approach chosen. For example, when a closed chest approach is used such as a port access approach wherein the device is introduced into the body cavity through a small access port or stab wound, the device must be designed to be advanced through such small openings without damaging the device or any internal body structures. A continuing need remains for new and better instruments that are capable of being delivered through small openings and still function satisfactorily in a closed-chest environment.
Furthermore, in addition to addressing delivery problems of instruments though small access openings, the working space within a closed-chest surgical environment is extremely limited, allowing much less room to maneuver the instruments, as compared to the space provided in an open-chest surgical site, once they have been successfully delivered or placed in the operative site. Thus, new and better approaches, tools and techniques for controlling instruments in a closed chest environment are needed.
As such, there is continued interest in the development of new devices and methods for easily and effectively stabilizing or immobilizing tissue, e.g., a beating heart, in a limited space environment, such as occurs during closed-chest procedures. Of particular interest would be the development of such devices and methods of use which may be used in a variety of surgical approaches, including a sternotomy, mini-sternotomy, thoracotomy, mini-thoracotomy, transabdominal entry, and particularly in less invasive techniques such as endoscopic or port access procedures (e.g., between the ribs or in a subxyphoid area), with or without the visual assistance of a thoracoscope. Similar interest exists for the development of devices that are operable in other reduced-access surgical environments within a patient.